Advice please about my Crf cat

[IlovemyPeedee]

All this is new to me and I am looking for any info or advice on what I should try. My Persian Peedee who will be 15 in April has renal failure. I took him to the vet yesterday for testing.I had noticed he had lost weight,then going to the bathroom outside letterbox and just looking like he doesn't feel well. The vet gave me the results of his lab work. His BUN was 152 creative 5.5 The vet couldn't believe he is still eating,but he is. She suggested fromatine? For his stomach and kidney diet wet food. She said I would know when it's time to put him asleep. Night time has been rough ,he constantly gets out of bed to get water which his bowl is in my bathroom then comes back and cries for me to lift him back in bed. We do this many times through the night. Needless to say we don't get much sleep. He has starting peeing in my bedroom which he usually would never do. He doesn't have a uti so it must be the Crf causing it. Obviously he doesn't feel well due to this.He still loves to be petted ,he sleeps most of the day. When he urinates it's very clear like water due to his kidneys not functioning. He has lost 3 pounds over the past few years. Sorry I know I have rambled. I will appreciate Any advice and suggestions. Thank you.